Fix write path
This commit is contained in:
parent
4ab9862ccb
commit
199d3fd79f
|
@ -115,14 +115,26 @@ func (ib *intraBlock) IsPartial() bool {
|
||||||
return false
|
return false
|
||||||
}
|
}
|
||||||
|
|
||||||
// ciphertextRange - get byte range in ciphertext file corresponding to BlockNo
|
// CiphertextRange - get byte range in ciphertext file corresponding to BlockNo
|
||||||
|
// (complete block)
|
||||||
func (ib *intraBlock) CiphertextRange() (offset int64, length int64) {
|
func (ib *intraBlock) CiphertextRange() (offset int64, length int64) {
|
||||||
return ib.BlockNo * ib.fs.cipherBS, ib.fs.cipherBS
|
return ib.BlockNo * ib.fs.cipherBS, ib.fs.cipherBS
|
||||||
}
|
}
|
||||||
|
|
||||||
// CropBlock - crop a full plaintext block down to the relevant part
|
// PlaintextRange - get byte range in plaintext corresponding to BlockNo
|
||||||
|
// (complete block)
|
||||||
|
func (ib *intraBlock) PlaintextRange() (offset int64, length int64) {
|
||||||
|
return ib.BlockNo * ib.fs.plainBS, ib.fs.plainBS
|
||||||
|
}
|
||||||
|
|
||||||
|
// CropBlock - crop a potentially larger plaintext block down to the relevant part
|
||||||
func (ib *intraBlock) CropBlock(d []byte) []byte{
|
func (ib *intraBlock) CropBlock(d []byte) []byte{
|
||||||
return d[ib.Offset:ib.Offset+ib.Length]
|
lenHave := len(d)
|
||||||
|
lenWant := int(ib.Offset+ib.Length)
|
||||||
|
if lenHave < lenWant {
|
||||||
|
return d[ib.Offset:lenHave]
|
||||||
|
}
|
||||||
|
return d[ib.Offset:lenWant]
|
||||||
}
|
}
|
||||||
|
|
||||||
// Split a plaintext byte range into (possible partial) blocks
|
// Split a plaintext byte range into (possible partial) blocks
|
||||||
|
|
|
@ -55,6 +55,10 @@ func (fs *CryptFS) NewFile(f *os.File) *CryptFile {
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
func (be *CryptFS) PlainBS() int64 {
|
||||||
|
return be.plainBS
|
||||||
|
}
|
||||||
|
|
||||||
// DecryptName - decrypt filename
|
// DecryptName - decrypt filename
|
||||||
func (be *CryptFS) decryptName(cipherName string) (string, error) {
|
func (be *CryptFS) decryptName(cipherName string) (string, error) {
|
||||||
|
|
||||||
|
|
|
@ -103,6 +103,9 @@ func (d *Dir) Remove(ctx context.Context, req *fuse.RemoveRequest) error {
|
||||||
|
|
||||||
func (d *Dir) Create(ctx context.Context, req *fuse.CreateRequest, resp *fuse.CreateResponse) (fusefs.Node, fusefs.Handle, error) {
|
func (d *Dir) Create(ctx context.Context, req *fuse.CreateRequest, resp *fuse.CreateResponse) (fusefs.Node, fusefs.Handle, error) {
|
||||||
fmt.Printf("Create\n")
|
fmt.Printf("Create\n")
|
||||||
|
|
||||||
|
req.Flags, _ = fixFlags(req.Flags)
|
||||||
|
|
||||||
req.Name = d.crfs.EncryptPath(req.Name)
|
req.Name = d.crfs.EncryptPath(req.Name)
|
||||||
n, _, err := d.Dir.Create(ctx, req, resp)
|
n, _, err := d.Dir.Create(ctx, req, resp)
|
||||||
if err != nil {
|
if err != nil {
|
||||||
|
|
|
@ -10,13 +10,40 @@ import (
|
||||||
"golang.org/x/net/context"
|
"golang.org/x/net/context"
|
||||||
)
|
)
|
||||||
|
|
||||||
|
func fixFlags(flags fuse.OpenFlags) (fuse.OpenFlags, bool) {
|
||||||
|
fmt.Printf("fixFlags: Before: %s\n", flags.String())
|
||||||
|
var writeOnly bool
|
||||||
|
// We always need read access to do read-modify-write cycles
|
||||||
|
if flags & fuse.OpenWriteOnly > 0 {
|
||||||
|
flags = flags &^ fuse.OpenWriteOnly
|
||||||
|
flags = flags | fuse.OpenReadWrite
|
||||||
|
writeOnly = true
|
||||||
|
}
|
||||||
|
// We also cannot open the file in append mode, we need to seek back for RMW
|
||||||
|
flags = flags &^ fuse.OpenAppend
|
||||||
|
fmt.Printf("fixFlags: After: %s\n", flags.String())
|
||||||
|
return flags, writeOnly
|
||||||
|
}
|
||||||
|
|
||||||
|
func max(x int, y int) int {
|
||||||
|
if x > y {
|
||||||
|
return x
|
||||||
|
}
|
||||||
|
return y
|
||||||
|
}
|
||||||
|
|
||||||
type File struct {
|
type File struct {
|
||||||
*cluefs.File
|
*cluefs.File
|
||||||
crfs *cryptfs.CryptFS
|
crfs *cryptfs.CryptFS
|
||||||
|
// Remember if the file is supposed to be write-only
|
||||||
|
writeOnly bool
|
||||||
}
|
}
|
||||||
|
|
||||||
func (f *File) Open(ctx context.Context, req *fuse.OpenRequest, resp *fuse.OpenResponse) (fusefs.Handle, error) {
|
func (f *File) Open(ctx context.Context, req *fuse.OpenRequest, resp *fuse.OpenResponse) (fusefs.Handle, error) {
|
||||||
fmt.Printf("File.Open: f.crfs=%p\n", f.crfs)
|
fmt.Printf("File.Open\n")
|
||||||
|
|
||||||
|
req.Flags, f.writeOnly = fixFlags(req.Flags)
|
||||||
|
|
||||||
h, err := f.File.Open(ctx, req, resp)
|
h, err := f.File.Open(ctx, req, resp)
|
||||||
if err != nil {
|
if err != nil {
|
||||||
return nil, err
|
return nil, err
|
||||||
|
@ -29,32 +56,68 @@ func (f *File) Open(ctx context.Context, req *fuse.OpenRequest, resp *fuse.OpenR
|
||||||
}
|
}
|
||||||
|
|
||||||
func (f *File) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadResponse) error {
|
func (f *File) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadResponse) error {
|
||||||
fmt.Printf("File.Read: f.crfs=%p\n", f.crfs)
|
|
||||||
iblocks := f.crfs.SplitRange(req.Offset, int64(req.Size))
|
iblocks := f.crfs.SplitRange(req.Offset, int64(req.Size))
|
||||||
for _, ib := range iblocks {
|
for _, ib := range iblocks {
|
||||||
var partReq fuse.ReadRequest
|
var partReq fuse.ReadRequest
|
||||||
var partResp fuse.ReadResponse
|
var partResp fuse.ReadResponse
|
||||||
o, l := ib.CiphertextRange()
|
o, l := ib.CiphertextRange()
|
||||||
|
partReq.Offset = o
|
||||||
partReq.Size = int(l)
|
partReq.Size = int(l)
|
||||||
partResp.Data = make([]byte, int(l))
|
partResp.Data = make([]byte, int(l))
|
||||||
partReq.Offset = o
|
|
||||||
err := f.File.Read(ctx, &partReq, &partResp)
|
err := f.File.Read(ctx, &partReq, &partResp)
|
||||||
if err != nil {
|
if err != nil {
|
||||||
return err
|
return err
|
||||||
}
|
}
|
||||||
plaintext, err := f.crfs.DecryptBlock(partResp.Data)
|
plaintext, err := f.crfs.DecryptBlock(partResp.Data)
|
||||||
if err != nil {
|
if err != nil {
|
||||||
fmt.Printf("Read: Block %d: %s\n", ib.BlockNo, err.Error())
|
fmt.Printf("Read: Error reading block %d: %s\n", ib.BlockNo, err.Error())
|
||||||
return err
|
return err
|
||||||
}
|
}
|
||||||
plaintext = ib.CropBlock(partResp.Data)
|
plaintext = ib.CropBlock(plaintext)
|
||||||
resp.Data = append(resp.Data, plaintext...)
|
resp.Data = append(resp.Data, plaintext...)
|
||||||
}
|
}
|
||||||
return nil
|
return nil
|
||||||
}
|
}
|
||||||
|
|
||||||
func (f *File) Write(ctx context.Context, req *fuse.WriteRequest, resp *fuse.WriteResponse) error {
|
func (f *File) Write(ctx context.Context, req *fuse.WriteRequest, resp *fuse.WriteResponse) error {
|
||||||
|
fmt.Printf("File.Write\n")
|
||||||
|
resp.Size = 0
|
||||||
iblocks := f.crfs.SplitRange(req.Offset, int64(len(req.Data)))
|
iblocks := f.crfs.SplitRange(req.Offset, int64(len(req.Data)))
|
||||||
iblocks = iblocks
|
var blockData []byte
|
||||||
|
for _, ib := range iblocks {
|
||||||
|
if ib.IsPartial() {
|
||||||
|
// RMW
|
||||||
|
blockData = make([]byte, f.crfs.PlainBS())
|
||||||
|
var readReq fuse.ReadRequest
|
||||||
|
var readResp fuse.ReadResponse
|
||||||
|
o, l := ib.PlaintextRange()
|
||||||
|
readReq.Offset = o
|
||||||
|
readReq.Size = int(l)
|
||||||
|
err := f.Read(ctx, &readReq, &readResp)
|
||||||
|
if err != nil {
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
copy(blockData, readResp.Data)
|
||||||
|
copy(blockData[ib.Offset:ib.Offset+ib.Length], req.Data)
|
||||||
|
blockLen := max(len(readResp.Data), int(ib.Offset+ib.Length))
|
||||||
|
blockData = blockData[0:blockLen]
|
||||||
|
} else {
|
||||||
|
blockData = req.Data[0:f.crfs.PlainBS()]
|
||||||
|
}
|
||||||
|
ciphertext := f.crfs.EncryptBlock(blockData)
|
||||||
|
var partReq fuse.WriteRequest
|
||||||
|
var partResp fuse.WriteResponse
|
||||||
|
o, _ := ib.CiphertextRange()
|
||||||
|
partReq.Data = ciphertext
|
||||||
|
partReq.Offset = o
|
||||||
|
err := f.File.Write(ctx, &partReq, &partResp)
|
||||||
|
if err != nil {
|
||||||
|
fmt.Printf("Write failure: %s\n", err.Error())
|
||||||
|
return err
|
||||||
|
}
|
||||||
|
// Remove written data from the front of the request
|
||||||
|
req.Data = req.Data[len(blockData):len(req.Data)]
|
||||||
|
resp.Size += len(blockData)
|
||||||
|
}
|
||||||
return nil
|
return nil
|
||||||
}
|
}
|
||||||
|
|
Loading…
Reference in New Issue